- 1). Engage the parking brake and turn off the ignition of your Audi A4.
- 2). Open the trunk and locate the small round plastic piece that covers the bolt securing the taillight assembly. Remove this piece by peeling it back with your hand.
- 3). Detach the bolt by turning it counterclockwise with a socket and a ratchet. Place the bolt aside for use later during reinstallation. Pull the taillight assembly out from the back of the vehicle.
- 4). Insert the new taillight assembly by sliding it into the taillight opening. Secure the assembly by inserting the bolt and turning it clockwise with a socket and a ratchet until it is tightened. Replace the plastic bolt cover.
- 5). Close the trunk. Test the new taillight to make sure that you have assembled it properly.
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